1. Field of the Invention
The present invention relates to a digital broadcast system. More particularly, the present invention relates to a method and apparatus for processing streaming data of content in a digital broadcast system supporting Video On Demand (VOD) service.
2. Description of the Related Art
Video On Demand (VOD) is a service that allows users to select and watch/listen to video or audio content on demand. Unlike a unidirectional broadcast service provided by a terrestrial broadcast or cable broadcast system, the VOD service is a bidirectional service that provides the subscriber with the content selected by the subscriber at the time selected by the subscriber.
A digital broadcast system supporting VOD service includes a content server, at least one set-top box, a network, and at least one content player. The content server stores VOD contents and transmits the content requested by a subscriber to the set-top box of the subscriber. The set-top box is responsible for recovering and playing the content transmitted in compressed form and for sending the subscriber's request to the content server. The network interconnects the content server and the set-top box. The content player plays the content data supplied by the set-top box.
The set-top box provides various functions for playing the content downloaded from the content server. The set-top box executes commands such as play, pause, fast forward, fast reverse, and skip that are input by means of a remote control or keys provided on a User Interface of a terminal.
The set-top box can be configured to provide the VOD service in various content playback schemes. For example, the set-top box can be configured to provide a VOD service in which the content is received in streaming data format and played immediately. The set-top box also can be configured to provide a VOD service in which the content received in streaming data format is stored and then the stored content is played at a later time.
In case of the store-and-play VOD service, the set-top box stores the received content in a storage device having a large storage capacity such as an internal or external hard disk. Typically, the hard disk has a storage space large enough to store the received content such that the set-top box stores the entire data of content and then provides the VOD service.
While there is no problem when the data size of the entire content downloaded from the content server is less than the storage capacity of the storage device, there is a problem when the data size of downloaded content is greater than the storage capacity. This causes a storage space shortage problem, resulting in failure of VOD service.